Ivabradine for the Treatment of Postural Orthostatic Tachycardia Syndrome: A Systematic Review.

Introduction: Postural orthostatic tachycardia syndrome (POTS) impacts millions of patients, but there is currently no gold standard treatment for this condition. Ivabradine is a novel heart rate (HR) lowering agent that acts on the sinoatrial node cells by selectively inhibiting the If-current.

Objective: The objective of this systematic review is to evaluate the evidence for the efficacy and safety of ivabradine for the treatment of POTS.

Methods: MEDLINE (from 1956 to August 2017) and EMBASE (from 1957 to August 2017) were queried with the following search term: "postural orthostatic tachycardia syndrome" OR "postural tachycardia syndrome" OR "chronic orthostatic intolerance" AND "ivabradine." Articles in English with clinical outcomes of human patient(s) treated with ivabradine for POTS were included.

Results: The initial search identified 73 articles. After screening, 13 articles were included. Two prospective open-label trials, three retrospective cohort studies, and eight case reports evaluated the safety and efficacy of ivabradine in a total of 132 patients with postural tachycardia. Overall, ivabradine lowered HR and provided symptomatic relief of POTS without blood pressure lowering. Dizziness, nausea, headache, and fatigue were the most common side effects and often did not lead to discontinuation of treatment.

Conclusion: Based on this small sample, ivabradine appears to be a reasonable option for patients with POTS who have failed or are unable to tolerate other treatment options, however, but a randomized controlled trial in this population is needed.